In the Lancet, Jan. 31, 2009, Dr. Emanuel and co-authors presented a “complete lives system” for the allocation of very scarce resources, such as kidneys, vaccines, dialysis machines, intensive care beds, and others. “One maximizing strategy involves saving the most individual lives, and it has motivated policies on allocation of influenza vaccines and responses to bioterrorism. . . . Other things being equal, we should always save five lives rather than one.

“However, other things are rarely equal—whether to save one 20-year-old, who might live another 60 years, if saved, or three 70-year-olds, who could only live for another 10 years each—is unclear.” In fact, Dr. Emanuel makes a clear choice: “When implemented, the complete lives system produces a priority curve on which individuals aged roughly 15 and 40 years get the most substantial chance, whereas the youngest and oldest people get changes that are attenuated (see Dr. Emanuel’s chart nearby).